I’ve read various articles debating the importance of the 1080p. I want to set the record straight once and for all: if you are serious about properly setting up your viewing room, you will definitely benefit from 1080p (and even 1440p.) Why? Because the 1080p resolution is the first to deliver enough detail to your eyeball when you are seated at the proper distance from the screen. But don’t just take my word for it: read on for the proof.

There are a few obvious factors to being able to detect resolution differences: the resolution of the screen, the size of the screen, and the viewing distance. To be able to detect differences between resolutions, the screen must be large enough and you must sit close enough. So the question becomes “How do I know if need a higher resolution or not?”. Here is your answer.

Based on the resolving ability of the human eye, it is possible to estimate when the differences between resolutions will become apparent. A person with 20/20 vision can resolve 60 pixels per degree, which corresponds to recognizing the letter “E” on the 20/20 line of a Snellen eye chart from 20 feet away. Using the Home Theater Calculator spreadsheet as a base, I created a chart showing, for any given screen size, how close you need to sit to be able to detect some or all of the benefits of a higher resolution screen. (Click the picture below for a larger version.)

What the chart shows is that, for a 50-inch screen, the benefits of 720p vs. 480p start to become apparent at viewing distances closer than 14.6 feet and become fully apparent at 9.8 feet. For the same screen size, the benefits of 1080p vs. 720p start to become apparent when closer than 9.8 feet and become full apparent at 6.5 feet. In my opinion, 6.5 feet is closer than most people will sit to their 50″ plasma TV (even through the THX recommended viewing distance for a 50″ screen is 5.6 ft). So, most consumers will not be able to see the full benefit of their 1080p TV.

However, front projectors and rear projection displays are a different story. They make it very easy to obtain large screen sizes. Plus, LCD and Plasma displays are constantly getting larger and less expensive. In my home, for example, I have a 123-inch screen and a projector with a 1280×720 resolution. For a 123-inch screen, the benefits of 720p vs. 480p starts to become apparent at viewing distances closer than 36 feet(14 feet behind my back wall) and become fully apparent at 24 feet(2 feet behind my back wall). For the same screen size, the benefits of 1080p vs. 720p start to become apparent when closer than 24 feet and become full apparent at 16 feet (just between the first and second row of seating in my theater). This means that people in the back row of my home theater would see some improvement if I purchased a 1080p projector and that people in the front row would notice a drastic improvement. (Note: the THX recommended max viewing distance for a 123″ screen is 13.7 feet).

So, how close should you be sitting to your TV? Obviously, you need to look at your room and see what makes sense for how you will be using it. If you have a dedicated viewing room and can place seating anywhere you want, you can use this chart as a guideline. It’s based on THX and SMPTE specifications for movie theaters; the details are available in the Home Theater Calculator spreadsheet.

Looking at this chart, it is apparent that 1080p is the lowest resolution to fall within the recommended seating distance range. Any resolution less than 1080p is not detailed enough if you are sitting the proper distance from the screen. For me and many people with large projection screens, 1080p is the minimum resolution you’d want.

In fact, you could probably even benefit from 1440p. If you haven’t heard of 1440p, you will. Here’s a link to some info on Audioholics.com. It is part of the HDMI 1.3 spec, along with 48-bit color depth, and will probably surface for the public in 2009 or so. You’ll partially be able to see the benefits of 1440p at the THX Max Recommended viewing distance and the resolution benefits will be fully apparent if you are just a little closer. I’ve read of plans for resolutions reaching 2160p but I don’t see any benefit; you’d have to sit too darn close to the screen to notice any improvement. If you sit too close, you can’t see the far edges of the screen.

In conclusion

If you are a videophile with a properly setup viewing room, you should definitely be able to notice the resolution enhancement that 1080p brings. However, if you are an average consumer with a flat panel on the far wall of your family room, you are not likely to be close enough to notice any advantage. Check the chart above and use that to make your decision.

ISF states the the most important aspects of picture quality are (in order): 1) contrast ratio, 2) color saturation, 3) color accuracy, 4) resolution. Resolution is 4th on the list and plasma is generally superior to LCD in all of the other areas (but much more prone to reflections/glare.) So pick your display size, then measure your seating distance, and then use the charts above to figure out if you would benefit from the larger screen size. So be sure to calibrate your screen! I recommend the following for calibration.

“I don’t like reading charts – just tell me what resolution I need”

If you don’t like reading charts and are looking for a quick answer, enter you screen size below to see how close you’ll need to sit to fully appreciate various screen resolutions.

Enter screen size: inches diagonal

For 480p (720×480) resolution, you must sit:
feet or closer to see all available detail

For 720p (1280×720) resolution, you must sit:
feet or closer to see all available detail

For 1080p (1920×1080) resolution, you must sit:
feet or closer to see all available detail

For 4k (3840×2160) resolution, you must sit:
feet or closer to see all available detail

For 8k (7680×4320) resolution, you must sit:
feet or closer to see all available detail

Note about “or closer” viewing distances calculated above: if you sit closer than the distances shown above, you will be able to see some (but not all) of the detail offered by the next higher resolution.

861 Comments

Thanks for a VERY useful site, Carlton, which I have used several times since HD TV sets came out some years back. Just replaced a 5 year old 50″ plasma set (that developed a horizontal line) with another 51″ plasma set, 720p, ($399), same brand (it was easy to put all the connections in the same places and not have to use a different remote). Our eyes are 9 to10 feet from the screen, and according to your excellent charts and calculator, we would not be able to see any difference between this set and a 1080p set costing several hundred dollars more! Thanks for helping me keep money in my pocket, and keep up the good work!

I, too, love the image quality of “deep” black levels of plasma sets. I also enjoy the fast refresh rates (much less fast action “smudging” than LCD’s or LED’s, to my eyes) and the wide viewing angles of plasma sets. It seems to me that 50″ plasma sets, for the buyer, are the financial “sweet spot” in HDTV sets at the present time; I’m sorry they’re going away.

I will give the edge to Plasma on response and viewing angle and even price. But each of those advantages is small and rapidly diminishing.

In fact, the cost advantage is due primarily to a fire sale, lately. Higher cost for both tooling and building. Manufacturers are trying to milk out the last potential for recovery of their expenses.

In the past two years, LED TVs (especially LG and Visio in my opinion), have nailed rich blacks with terrific “selective dimming” capability. The result is stunning. I would have thought that it might cut the shadow detail to achieve improved contrast, but if this is the case, I certainly cannot detect the loss.

Now, consider the disadvantages:
a) 5~7 year operational life compared to 25 years or more
b) Consumes more power
c) Start up delay (not sure… please comment)
d) Much bulkier unit than newer LEDs

Yea right dude.. I had a plasma TV for years and ended up giving it away.. Recently bought a led…horrible motion blur.. So bad it hurt my eyes i dont know who in there right mind would want an led over plasma..in the case of motion blur and smooth image, plasma simply cannot be matched the way the plasma screen produces the image that enables it to refresh the image so much faster than a led

I have a Panasonic 42″ 480p plasma that is now 15 years old, and still looks superb. It’s been retired to my office on broadcast digital TV/DVD duty, and been replaced in the living room with a Panasonic ZT 60″. When I had the ZT ISF calibrated by the same guy who did my 42″ years ago, he said it had barely changed in all that time when he measured it for a calibration top-up.

What’s germane to the topic is the resolution of the eye, not the focus. Our eye simply does not have the “resolution receptors” to detect the amount of lines that are present in the higher resolution displays at a specific distance.

Without getting too far away from the subject of this being an awesome site, Ben G is right that normally sighted people have slightly better than 20/20. (read SLIGHTLY). But really, this is a linear ratio, so anyone who wants to use the above chart with their visual acuity, just do the following.

I am thinking of building out a piece of my basement to create a small home theater. (8’Wx13’Lx7’2″H Looking to get two sets of two seats and a sound system and maybe a 4K Tv. Any ideas on brands and specific products that could fit this small space yet give me a quality experience and keep the wife happy as well.

I’m confused. When I tried your calculator, for a 24″ 720p tv, it says I must sit 5 feet or CLOSER for full benefit. I thought the closer you sit to a lower resolution screen the less sharp the picture is compared to a 1080p? Thus it would seem that sitting 5 feet or FARTHER would make the differences between 720p and 1080p less apparent.
???

I see where you are confused… The closer you sit to any raster or dot matrix image, the more you are likely to discern the individual pixels. But, I wouldn’t characterize this as “less sharp”. The sharpness doesn’t change with viewing distance…

But, for any image dpi, there is a distance past which your eyes cannot see the benefit of HIGHER dpi (or more lines of a fixed width screen). This is just a matter of anatomy. Your retina (or eye-brain apparatus) has a maximum resolution. Carlton’s calculator helps you to find that benefit cliff. Past that distance, spending money on resolution is wasted, because you cannot enjoy the extra pixels—UNLESS you plan to occasionally use the projector or screen at other sizes or distances. In that case, the extra resolution can’t hurt.

Since a lot of people, specially gamers, are looking into 4K monitors nowadays, they don’t realize that they won’t actually benefit from that high resolution with a 27″ display. Id say 27″ monitor is best with 1440p if you are sitting 3-4′ away. If you really want 4K, then make sure you either buy a 40″ screen or stay heck close to it! Won’t people learn at last? It’s like a “need” for more without realizing you are throwing money at some crap.

I agree that 4k is focused more on selling higher specs than on providing true user benefit. Computer monitors are the best use case, but unfortunately many graphics cards can’t produce reasonable frame rates at such high resolutions.

(I realize it’s an old thread, so the direct second person address is rhetorical – I don’t expect an answer.) You’re sitting 3′-4′ away from your monitor? Does “gamers” refer specifically to console gamers, who are likelier to be playing on a TV as opposed to seated at a desk? If so, anything above 1080 is wasted, since consoles for at least the next generation or two (even now, in 2017) won’t be able to handle above 1080p rendering while staying withing their target price points. If you’re talking about PC gaming, the PC gamers I know usually have setups sitting 1′-2′ from the monitor, and 2′ is the maximum distance suggested to see the full benefit of 2160p on a 27″ screen, which does allow for real benefit from 2160p. I’m not questioning the reasonableness of your preference – whatever works for you is great, and I (with a 27″ monitor about 2′ away from me) similarly decided that any possible benefit from 2160p over 1440p was not nearly worth the money, especially given the lack of content (GPU rendering limits, at least without sinking several thousand dollars into hardware, and still few 4K TV/movie offerings plus ISP bandwidth/data caps limiting utility and financial viability of streaming higher-resolution content). But based on what’s presented here, there is actual benefit to be had for a lot of PC gamers playing games at a desk to going up to 2160p, if they have the cash and inclination.

Hi, Carlton,
Thanks for the post, it is really helpful.
I have a question regarding choosing a projector. The resolution of my film is 720p (1280×720) and I would like to screen it in its best quality.
There are two projectors I can choose:
one is 1280×800, 4000 lumens
another is1920x1200, 4200 lumens

If money is not an issue, which one will give better image quality for my 1280×720 film?

Do you have any reviews or info on which Manufactures make the BEST “Smart” TVs, including Picture Quality and Less Complications using {if this rating exists}?Lol! Sorry, when it comes to “Computer Technology”, I am not very literate. I would appreciate any info you can provide would be very useful when I go shopping next week! Thank-you, Kelly

Hi Carlton. Thanks for this article. It is the most informative / detailed I’ve seen yet on this topic. I plan on having roughly a 100 inch(diagonal) 16:9 screen and sitting roughly 10 feet from the screen. Do you feel I would I notice the difference between 1080 and 720 based on those parameters? Thanks!

What about 1080i compared to 720p, is there a big difference? Or is it just about the same as 1080p? Because most if all tv stations broadcast 1080i signals, so the only true 1080p picture would be blu ray, so my question is, would there be any big difference between 1080i and 720p? If so would the distance still be 10 feet?

1080i vs 1080P is also something your eye cannot see the difference in either.

1080i the even lines are drawn, then the odd ones @ 120Hz, 1080p the entire screen is drawn one frame at a time @ 120 Hz. In fact most players slow the draw cycle down to only 24Hz, ever see this; 1080P 24 . That’s to deliberately done to give the movie theater affect BEFORE digital projectors when film was used. Your human eyeball can only really see or process just about 22 Hz any way.

Don’t succumb to the hype of 4K or 240 Hz! 4K will never be used by broadcast TV. There simply is not enough bandwidth to provide the signal, yet. 1080 5.1 needs 6Mb/s download, 4k, needs 24 Mb/s. Guess what also, 4K is only at 30 Hz also!

The ONLY place 4K is good for is computer monitors. 1, it’s the only environment where your eye balls are close enough to see the resolution. 2. A direct connection to the data stream is only possible on a computer, for now.

Plug a laptop into a TV. Turn everything on at set resolution to 1080. Now bring up any Web page. Finally go sit where you normally sit to watch TV. CAN you read anything on the page? 99% of the time absolutely not at all.

Two years ago, I wrote an article, “Is 4K TV Relevant?”http://awildduck.com/?p=2755
Just as with this page by Carlton Bale, it was among the most popular in my own Blog.

I questioned the need for 4K for the same reasons that Carlton discusses: Resolution -vs- distance compared to ocular physiology. My original conclusion was that at a normal TV viewing distance, 4K would not be perceived, nor would it increase enjoyment. I recommended putting the money and effort into a better sound system, better black levels, or redecorating the room to be a theater-style shadow box.

If you scroll through the comments to my article, you will see that I have completely retracted that opinion. 4K is very relevant and the benefits are worthwhile.

The assumptions that Carlton and I made concerning physiology were based on the packing density of rods in a human retina—and perhaps field tests of visual discrimination. But this fails to account for our ability to discriminate acutance, which is caused by lightwave diffraction and interference. Your brain can perceive acutance far beyond the grid resolution of a subtended angle.

Whether it is because of our enhanced ability to discriminate acutance or perhaps an effect of combined motion, color & resolution, I am now certain that 4K enhances television experience over 1080p—even at a distance. And it is more than just a marginal gain.

I also refute Jason’s analysis of progressive -vs- interlaced and his statements about 24fps -vs- scan rates of 60, 120 or 240. Although the interaction of frame rate and scan rate must be considered when transcoding or viewing media, these are *NOT* the same or even comparable things. A TV scan rate or motion index of 240 provides a very tangible benefit for sports and fast moving scenes, especially if the original event was shot direct to video with the same parameters. The issue is not whether the eye can sense jitter at a fast rate, but whether the recorded image is a collection of still frames or it actually tracked a moving ball’s motion by painting its true position in real time.

And incidentally, most individuals can see an annoying flicker at any frame rate less than 120 Hz. For this reason, fluorescent light ballasts use full wave rectifiers (if the voltage converter does not chop at high speed for reasons of trasnsforner efficiency). For this same reason, 60Hz TVs are built with long-glowing phosphors.

And even with long-glow phosphor, these TVS may fool the eye into thinking that the picture is retained, but they still leave the brain unsatisfied, because the motion is stuttered. Of course, this is not typically a problem, because (as Jason points out) the original media is at 24 or 32 fps.

No, 4K with a 4K BD (Due out this year) will be very visible on these TVs and it doesn’t require a 24 Meg feed to view 4K video. Sorry but, even 1080P can be streamed at a decent quality with a 3 Meg stream and 4K can be achieved with about an 8 to 10 Meg stream.

Now as for the claims about 120 – 600 Hz, those pushing these points are basically ignoring the fact that much of the data is being generated on the fly with filler frames and thus, it isn’t real regardless of how sharp it appears. Yes it is great to see sharp edges to your on screen objects but, it isn’t 100% natural.

Why didn’t you cover the extinction point where details become muddled. Truth is, your numbers are ambiguous.

Yes your starting numbers are correct but, reality is that any screen between 50″ and 70″ and you won’t be able to discern the individual pixels if you’re sitting 9′ to 10′ from the screen so your max numbers are irrelevant for the most part.

As far as I am concerned movie or TV show enjoyment depends on the following in this order, content, sound and then visuals. Lets face it, these days media offerings suck. I don’t care how big your video is, how deep your resolution or how many sound channels you have, a movie or TV show that sucks will still suck. It has been proven that better sound is more important to how much you enjoy a program than video. So I’d rather spend money on properly decoded 7.1 than a bigger screen.

Referring to John Casey’s comment, all of these things (content, video quality, sound quality) are personal and subjective. As qualitative components of “enjoyment”, it is unlikely that one could demonstrate the claim “It has been proven that better sound is more important than video.”

1. The comment about content quality is a red herring. If each individual visiting this page didn’t have at least some content that he/she found enjoyable, they wouldn’t be here and they wouldn’t have built a home theater. No one says that the content has to be from Hollywood or of this century. C’mon! Surely, you acknowledge that there are some films or documentaries worth watching or sharing with friends!

2. Sound is certainly important to the theater experience. In fact, I tend to place it higher than moving beyond HD resolution. But to say that it is “more important” than video is somewhat meaningless. Is it more important, even if the choice is between upgrading already decent sound (but lacking a 2nd sub-woofer) -vs- upgrading a 180p video monitor at 15 fps?

3. In the past few months, I revisited and retracted my own post, which asserts no need for 4K: Is 4K HDTV relevant? http://awildduck.com/?p=2755 (that change of opinion is was acknowledged here at carltonbale.com and is also one of the more recent comments to my own article).

Although, I dispute that one can rank video, audio and content relative to each other, I believe that two factors are often overlooked and for many viewers can lead to a greatly improved experience: (a) Thundering bass, (b) Extreme blacks with super-wide dynamic range. For projection theater (as opposed to an active screen, such as LED or plasma), attaining (b) requires a screen with some gain (to avoid scattering) and a blackout box. This means painting the front 1/2 of your room a very flat black on all 4 surfaces. Without a black box, the contrast and dynamic range will be shot, because unlike a television screen, a projection screen is white.

I don’t speak for Carlton, but I feel that you are inferring something that is technically correct, yet in the real world, you are holding the wrong variable as dependent. It’s a but like mixing up cause and effect…

Yes: If you have two screens of the same size, and if one has a much higher pixel density, then would need to stand much closer to resolve those finer pixels.

But this misses the point! Carlton’s charts help you to figure out the screen size or distance at which the higher number of pixels make a meaningful contribution to your enjoyment. For example, they answer these questions:

1. I have a projector and screen that is HD (1920×1080) and 105″ (diagonal). I like to sit at the far end of the room which is 20 feet from the screen. My projector has lots of life remaining and it yields great focus, fast motion and deep blacks. Does it make sense for me to upgrade to a 4K projector?

2. I have a 4K projector and a 120″ screen (16×9 measured diaganol). How close must I sit to experience the benenfit of 4K over HD?

Good follow up questions to #2 would be: From the recommended max distance can I take in the entire screen with both eyes and without turning my head?

You can see that Carlton’s answers to these sample questions don’t demand that you sit closer to a screen with lots of pixels. They simply put boundaries on the benefits derived. In my opinion, they might lead more people to a larger viewing screen rather than a closer seating arrangement.

Hey. The Game Worldcraft keep crashing it’s view distance on my cellphone. Can you please help me? View distance is from 6. But here is the error message
LOW VIEW DISTANCE
View Distance Decreased From 6 To 5
Ok Change
When I Open The Game. The Message Shows. Not Every. Sometimes

Yeah sure mr troll just set your view distances with a trusty potato cam and view your screen through a bifocal lens dead centered on the blurry pixels screen. You need about 12 feet of running distance that should solve your problem!!!!!!!

This article puts the human eye resolution at around 0.3arc-min per pixel (or 200pixels per degree). If that’s the case then, in theory, the viewing distances could be over 3x what you’re quoting with the 60pix/degree calculations.

This is really useful information.
So does this mean it does not make any sense at all to by a 43″ UHD TV? I have viewing distance of about 10 ft.
I currently have a 43″ Full HD TV. Will I see any difference at all with at all with 43″ UHD TV from 10 ft?

I disagree, as I said in my comment above, the 60pixels per degree here is not the industry standard on human eye perception which is widely accepted as 0.3 to 0.4 arc min for good eyesight. This would mean you could see all the available detail at around 9ft from your 43” screen – not too far from your 10ft I would still expect you to be able to tell the difference – if you have good eyesight.
The best way to determine if it would make a difference for your eyes – go check it out in a store. Walk back from a side by side 1080p and 4k screen and see where the difference becomes negligible. Then scale that difference based on your screen size (i.e. if your screen 40 inches and the store screens were 60 inches then reduce the distance you got in the store by 40/60 or two thirds).